Many plant seeds or fruits, including peas, beans and nuts, require the removal of an exterior protective pod or shell prior to consumption. The term “unshelled” herein refers to legumes and nuts in their natural state; that is, when the legume or nut is still within its hull, pod or shell, wherein the empty hull, pod or shell is typically called “chaff”. As such, the term “shelled” herein refers to a legume or nut after its hull, pod or shell has been removed.
While removal of the pod or shell may be accomplished by hand, mechanical means provide for a reduction in labor, and often, an improvement in yield. Accordingly, various devices have been utilized to facilitate the removal of a hull, pod or shell by processing a bulk load of unshelled seeds and/or fruit, wherein the inner edible seeds and/or fruit portions are separated and removed from the outer inedible shell portions.
Removal of the pod/hull from legumes is particularly difficult because of the often soft composition of the pea, bean, or other legume. Therefore, devices have been developed to stroke the podded legume at a low rate of impact to remove the outer pod, hull or shell. In many such devices, legumes are rotated in a drum, wherein the pod impacts against paddles or other objects, and wherein the (pea or bean) legume exits the drum surface, while the chaff passes through the bore of the drum. Such rotating drum devices allow for flow-through of material over a period of time, with the legume dropping out through a screen or similar mechanism around the peripheral shell of the drum, while the chaff migrates through the drum and exits at one end thereof.
In such rotating drum shellers, selection of a suitable dwell time in the drum is important to improve yield. Too short a time, and whole pods will migrate through and exit the drum end, thereby reducing yield. Too long a time in the drum, and insufficient material will pass through the device in a given time to render it economically practical, and, further, the legume may suffer damage from repeated processing. Accordingly, baffle plates are often installed within the drum to control the flow of material through the drum.
One such existing baffle plate is fully circular but of a lesser diameter than the inner diameter of the drum, so as to provide a gap between the peripheral edge of the baffle and the inner drum wall. As such, unshelled legumes and chaff are delayed in transit, passing only through the gap. However, because unshelled or podded legumes will tend to flow to the outside of the baffle due to gravity and/or centrifugal force, such unshelled legumes are free to pass through the gap without adequate dwell time within the drum; thereby, providing proper removal of the hull, pod or shell.
Baffle partitions that fill the entire drum diameter have also been utilized to reduce the size of the drum for use with smaller loads. Unfortunately, such devices block the passage of the chaff out of the drum and, thus, defeat the ability to utilize the drum as a continuous-feed, flow-through device.
Therefore, it is readily apparent that there is a need for a sheller and method of use thereof, wherein the sheller adequately provides for flow through a drum, while selectively controlling dwell time.